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# OAR Box 1787 Prepped byOllie Stewart



### Document

Number: 

# 9DII-C-4 9 Docket Number: 

# A-90-3 7

Printed 11/4/200810:22:20 AM

Sheet 91 of 147P. 2 

# &M\-9&htfPttfct/

/Mo or - eNOTE : THI S I S A

PRELIMINAR

YSTAF F OUTLINE O F A DRAF T OPTIO

N THAT EP A I S EVALUATIN

GI N PREPARATIO

N O F A PROPOSEDRULEMAKING . THI S INTERPRETATIO

N I S NO T EP

A GUIDANC E ORPOLICYO N TH E ISSUE .

MODIFICATION S I NSERIOUS/SEVER E OZON E NONATTAINMENT AREA S
INTRODUCTION Th e amende d Ac t a t Section s 182(c)(6),(7 ) & (8 ) (cop y attached ) contain s specia l provision s fo r applying nonattainmen t NS R t o modification s a t existin g majo r stationarysource s o f volatil e organi c compound s (VOC ) presumptivel yNO x , locate d i n Seriou s o r Sever e ozon e nonattainmen t areas . an d

I n ou r upcomin g Par t C/ D NS R rulemakin g proposal , EPA intend s t o codif ythes e ne wspecia l provision s i n th e revise d nonattainmen t NS R rules . EPAi s evaluatin g severa l option s fo r implementing th e specia l provision s an d request s inpu t an d suggestion s fro

m th e FACArepresentative s o n th e issues . Sen d you r comment s b yAug . 16 , 199 3 t o Mik e Sewell , U.S . EPA , MD-15 , Ne wSourc e Revie wSection , RTP , N.C . 27711 .P. 3

NOTE : THI S I S A

PRELIMINAR

YSTAF F OUTLINE O F A DRAF T OPTIO

N THAT EP A I S EVALUATIN

GI N PREPARATIO

N O F A PROPOSEDRULEMAKING . THI S INTERPRETATIO

N I S NO T EP

A GUIDANC E ORPOLICYON TH E ISSUE .

IMPLEMENTATIO

N OPTIO N FO REVALUATIO

N STE P I "Increas e i n Ne t Emission s " fro mth e Propose d Modificatio n Th e specia l provision s appl yt o propose d modification s tha t resul t i n a n "increas e i n ne t emissions" . Th e "d e minimis " emission s rat e specifie d i n (c)(6 ) fo r determinin g NS R applicabilit yi s 2 5 tpy . Th e "increas e i n ne t emissions " calculatio n fo r a propose d modificatio n include s contemporaneou s decrease s tha t ar e par t o f th e propose d modification . Fo r suc hne t increase s o f 2 5 tpyo r less , th e specia l aggregatio n provision s o f (c)(6 ) apply . Fo r suc hne t increase s ove r 2 5 tpy , th e specia l provision s o f eithe r (c)(7 ) o r (c)(8 ) apply . Th e specia l provision s o f eithe r (c)(7 ) o r (c)(8 ) appl yt o an ydiscret e emission s unit(s ) wit han "increas e i n ne t emissions " ove r 2 5 tpy , regardles s o f othe r decrease s a t th e source . Fo r suc hunits , th e ne waggregatio n provision s o f (c)(6 ) d o no t apply . STE P I I Specia l Aggregatio n Provision s o f (c)(6 ) Th e aggregatio n provision s appl yt o propose d modification s wit ha n "increas e i n ne t emissions " o f 2 5 tpyo r less . T o determin e i f th e propose d modificatio n i s abov e th e "de minimis " cutoff , aggregat e th e "increas e i n ne t emissions " fromth e propose d modificatio n wit hal l othe r "ne t increases " a t th e sourc e ove r an yperio d o f 5 consecutiv e calenda r year s whic hinclude s th e calenda r yea r i n whic h suc hincreas e occurred . Previou s ne t decrease s woul d no t coun t here , bu t mayb e creditabl e a s interna l offset s whe n applyin g (c)(7 ) o r (c)(8) . 

# JNOTE : THI S I S A PRELIMINAR

YSTAF F OUTLINE OF A DRAF T OPTIO

N THAT EP A I S EVALUATIN

GIN PREPARATIO

N O F A PROPOSEDRULEMAKING . THI S INTERPRETATIO

N I S NO T EP

A GUIDANC E O

RPOLICYON

TH E ISSUE .
I f th e aggregate d ne t increas e i s ove r 2 5 tpy , th e specia l provision s o f eithe r (c)(7 ) o r (c)(8 ) apply . Th e provision s o f (c)(7 ) appl yt o existing majo r stationary source s emittin g <10 0 tpyan d th e provision s o f (c)(8 ) appl y t o existin g majo r stationarysource s emittin g >10 0 tpy .

STE P II I "Modification s A t Existing Source s Emitting <10 0 TPY " Sectio n (c)(7 ) allow s BAC T instea d o f LAER . Th e propose d modificatio n (o r discret e unit s tha t ar e par t o f th e modification ) avoi d nonattainmen t NS R i f th e emission s increas e i s offse t internall ya t a rati o o f a t leas t 1.3:1 .

STE P I V "Modification s A t Existin g Source s Emittin g > 10 0 TPY " Sectio n (c)(8 ) require s nonattainmen t NS R fo r th e propose d modification . A s a sourc e option , propose d modification s (o r discret e unit s tha t ar e par t o f th e modification ) mayb e exemp t fro m LAE R i f th e emission s increas e i s offse t internall ya t a rati o o f a t leas t 1.3:1 . Thi s optiona l exemptio n i s onl yfo r LAER , th e remaining nonattainmen t NS R requirement s stil l apply . Genera l NS R offset s shoul d b e obtaine d i n additio n t o th e interna l offsets .P. 5

Clea nAi r Ac t a s Amende d(1990 ) Section s 182(c)(6) , (7 ) & (8 )
(6 ) D e minimi s Rul e — Th e ne wsourc e revie wprovision s unde r thi s par t shal l ensur e tha t increase d emission s o f volatil e organi c compound s resultin g fro man yphysica l chang e in , o r chang e i n th e metho d o f operatio n of , a stationar ysourc e locate d i n th e are a shal l no t b e considere d d e minimi s fo r purpose s o f determinin g th e applicabilit yo f th e permi t requirement s establishe d b ythi s Ac t unles s th e increas e i n ne t emission s o f suc hai r pollutan t fro msuc hsourc e doe s no t excee d 2 5 ton s whe n aggregate d wit hal l othe r ne t increase s i n emission s fro mth e sourc e ove r an yperio d o f 5 consecutiv e calenda r year s whic h include s th e calenda r yea r i n whic hsuc hincreas e occurred . (7 ) Specia l Rul e fo r Modification s o f Source s Emittin g Les s than10 0 Ton s —I n th e cas e o f an ymajo r stationar ysourc e o f volatil e organi c compound s locate d i n th e are a (othe r tha n a sourc e whic hemit s o r ha s th e potentia l t o emi t 10 0 ton s o r mor e o f volatil e organi c compound s pe r year) , wheneve r an ychang e (a s describe d i n sectio n 111(a)(4) ) a t tha t sourc e result s i n an y increas e (othe r tha n a d e minimi s increase ) i n emission s o f volatil e organi c compound s fro man ydiscret e operation , unit , o r othe r pollutan t emittin g activit ya t th e source , suc hincreas e shal l b e considere d a modificatio n fo r purpose s o f sectio n 172(c)(5 ) an d sectio n 173(a) , excep t tha t suc hincreas e shal l no t b e considere d a modificatio n fo r suc hpurpose s i f th e owne r o r operato r o f th e sourc e elect s t o offse t th e increas e by a greate r reductio n i n emission s o f volatil e organi c compound s concerne d fro mothe r operations , units , o r activitie s withi n th e sourc e a t a n interna l offse t rati o o f a t leas t 1. 3 t o l . I f th e owne r o r operato r doe s no t mak e suc helection , suc hchang e shal l b e considere d a modificatio n fo r suc hpurposes , bu t i n applyin g sectio n 173(a)(2 ) i n th e cas e o f an ysuc hmodification , th e bes t availabl e contro l technolog y(BACT) , a s define d i n sectio n 169 , shal l b e substitute d fo r th e lowes t achievabl e emissio n rat e (LAER) . Th e Administrato r shal l establis han d publis hpolicie s an d procedure s fo r implementin g th e provision s o f thi s paragraph . (8 ) Specia l Rul e fo r Modification s o f Source s Emittin g 10 0 Ton s o r Mor e — I n th e cas e o f an ymajo r stationar ysourc e o f volatil e organi c compound s locate d i n th e are a whic hemit s o r ha s th e potentia l t o emi t 10 0 ton s o r mor e o f volatil e organi c compound s pe r year , wheneve r an ychang e (a s describe d i n sectio n 111(a)(4) ) a t tha t sourc e result s i n an yincreas e (othe r tha n a d e minimi s increase ) i n emission s o f volatil e organi c compound s fro man ydiscret e operation , unit , o r othe r pollutan t emittin g activit ya t th e source , suc hincreas e shal l b e considere d a modificatio n fo r purpose s o f sectio n 172(c)(5 ) an d sectio n 173(a) , excep t tha t i f th e owne r o r operato r o f th eP. 6

sourc e elect s t o offse t th e increas e b ya greate r reductio n i n emission s o f volatil e organi c compound s fromothe r operations , units , o r activitie s withi n th e sourc e a t a n interna l offse t rati o o f a t leas t 1. 3 t o l , th e requirement s o f sectio n 173(a)(2 ) (concerning th e lowes t achievabl e emissio n rat e (LAER) ) shal l no t apply .

# SPECIA L MODIFICATIO N PROVISION S FO R

SERIOU S &SEVER E OZON E NONATTAINMEN TAREAS

SEC . 182(c)(6),(7) , &(8) 

# Applie s t o modification s at existin g majo r stationar ysources o

fVO C an d NO x Significance leve l fo rmodifications , o r discrete unit(s) , i s > 2 5 tpy Opportunities t o avoi d Par t D NS R reviewo r LAE R i finterna l offset

s are obtaine d

# STE P I - "INCREAS E I N NE TEMISSIONS "

FRO M TH E PROPOSE D MODIFICATIO N

•Su m increases an d decreases fro m th e proposed modificatio n t o calculate th e "increas e i n ne t emissions "

- i fsu m i s 2 5 tp

yo rless , nettin g provision s o f (c)(6 ) appl y

- i fsu m i s > 2 5 tpy , provision s o f(c)(7 ) o r(c)(8 ) appl y 

# •Fordiscret

e unit(s ) wit h "increase

s i n ne t emissions " > 2 5 tpy , regardless o fan y decreases a

t othe runits , th e provision s o f (c)(7) o r(c)(8) appl y PtCAl

# STE P I I SUMMIN G "NE TINCREASES "

•Su m al l "ne

t increases " a

t source ove ra 5 yea rcontemporaneou s period
•Significance leve l is > 2 5 tpy
•Contemporaneou s period i s 5 consecutiv e calenda ryear

s whic h includes th e calenda r yea rwhe n increase wil l occu r
•Fo rsignificant increases

- (c) (7 ) applies t o existin g majo rsources < 100 tp y

- (c) (8) applies t o existin g majo rsources 10 0 tp yo rgreate r

C O

# KE YISSU E CREDITIN G DECREASE S "Current " Nettin g Optio n

- su m al l creditabl e increases an d decreases durin g th e contemporaneou s period "New " Nettin g Optio n

- onlysu m "ne

t increases " durin g th e contemporaneou s period

- creditabl e ne

t decreases ar

e availabl e a s interna l offset

s

# STE P II I



# SEC . 182(c)(7) PROVISION S MAJO R SOURCE S LESS THA N 10 0 TPY BACTapplie s instea d o fLAE R Par t D NS R doe s no

t appl yt o th e modification , o ran ydiscrete unit(s) , i f1.3: 1 interna l offset

s are obtaine d

r

# STE P IV



# SEC . 182(c)(8 ) PROVISION S MAJO R SOURCE S 10 0 TP YO R GREATE R Par t D NSR Applie

s A s a n option , LAER doe

s no t appl yto th e modification , oranydiscret e unit(s) , i

f1.3: 1 interna l offset

s ar e obtaine d

- Remainin g Par

t D NS R provision s stil l appl y

/fc f 3 

### It,«•^ 

# KE YISSU E OFFSE TREQUIREMEN TFO R LAE R OPTIO N Genera l Par

t D offse t requiremen t is :

- a t leas t 1.2: 1 fo rSeriou s ozon e areas

- a t leas t 1.3: 1 fo rSever

e ozon e area s 

# Does 1.3: 1 interna l offse t required whe n avoidin g LAE R satisf

yth e Genera l offse

t requirement ?

7